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Drake H, Ivarsson M, Bengtson S, Heim C, Siljeström S, Whitehouse MJ, Broman C, Belivanova V, Åström ME. Anaerobic consortia of fungi and sulfate reducing bacteria in deep granite fractures. Nat Commun 2017; 8:55. [PMID: 28676652 PMCID: PMC5496868 DOI: 10.1038/s41467-017-00094-6] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 05/31/2017] [Indexed: 11/08/2022] Open
Abstract
The deep biosphere is one of the least understood ecosystems on Earth. Although most microbiological studies in this system have focused on prokaryotes and neglected microeukaryotes, recent discoveries have revealed existence of fossil and active fungi in marine sediments and sub-seafloor basalts, with proposed importance for the subsurface energy cycle. However, studies of fungi in deep continental crystalline rocks are surprisingly few. Consequently, the characteristics and processes of fungi and fungus-prokaryote interactions in this vast environment remain enigmatic. Here we report the first findings of partly organically preserved and partly mineralized fungi at great depth in fractured crystalline rock (-740 m). Based on environmental parameters and mineralogy the fungi are interpreted as anaerobic. Synchrotron-based techniques and stable isotope microanalysis confirm a coupling between the fungi and sulfate reducing bacteria. The cryptoendolithic fungi have significantly weathered neighboring zeolite crystals and thus have implications for storage of toxic wastes using zeolite barriers.Deep subsurface microorganisms play an important role in nutrient cycling, yet little is known about deep continental fungal communities. Here, the authors show organically preserved and partly mineralized fungi at 740 m depth, and find evidence of an anaerobic fungi and sulfate reducing bacteria consortium.
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Affiliation(s)
- Henrik Drake
- Department of Biology and Environmental Science, Linnæus University, Kalmar, 39182, Sweden.
| | - Magnus Ivarsson
- Department of Palaeobiology and Nordic Center for Earth Evolution (NordCEE), Swedish Museum of Natural History, P.O. Box 50 007, Stockholm, 10405, Sweden
| | - Stefan Bengtson
- Department of Palaeobiology and Nordic Center for Earth Evolution (NordCEE), Swedish Museum of Natural History, P.O. Box 50 007, Stockholm, 10405, Sweden
| | - Christine Heim
- Geoscience Centre Göttingen of the Georg-August University (Department of Geobiology), Goldschmidtstr. 3, Göttingen, 37077, Germany
| | - Sandra Siljeström
- Department of Surfaces, Chemistry and Materials, SP Technical Research Institute of Sweden, P.O. Box 857, Borås, 50115, Sweden
| | - Martin J Whitehouse
- Department of Geosciences and Nordic Center for Earth Evolution (NordCEE), Swedish Museum of Natural History, P.O. Box 50007, Stockholm, 10405, Sweden
| | - Curt Broman
- Department of Geological Sciences, Stockholm University, Stockholm, 106 91, Sweden
| | - Veneta Belivanova
- Department of Palaeobiology and Nordic Center for Earth Evolution (NordCEE), Swedish Museum of Natural History, P.O. Box 50 007, Stockholm, 10405, Sweden
| | - Mats E Åström
- Department of Biology and Environmental Science, Linnæus University, Kalmar, 39182, Sweden
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Gonzalez-Gil G, Sougrat R, Behzad AR, Lens PNL, Saikaly PE. Microbial community composition and ultrastructure of granules from a full-scale anammox reactor. Microb Ecol 2015; 70:118-31. [PMID: 25501888 DOI: 10.1007/s00248-014-0546-7] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Accepted: 11/27/2014] [Indexed: 05/10/2023]
Abstract
Granules in anammox reactors contain besides anammox bacteria other microbial communities whose identity and relationship with the anammox bacteria are not well understood. High calcium concentrations are often supplied to anammox reactors to obtain sufficient bacterial aggregation and biomass retention. The aim of this study was to provide the first characterization of bacterial and archaeal communities in anammox granules from a full-scale anammox reactor and to explore on the possible role of calcium in such aggregates. High magnification imaging using backscattered electrons revealed that anammox bacteria may be embedded in calcium phosphate precipitates. Pyrosequencing of 16S rRNA gene fragments showed, besides anammox bacteria (Brocadiacea, 32%), substantial numbers of heterotrophic bacteria Ignavibacteriacea (18%) and Anaerolinea (7%) along with heterotrophic denitrifiers Rhodocyclacea (9%), Comamonadacea (3%), and Shewanellacea (3%) in the granules. It is hypothesized that these bacteria may form a network in which heterotrophic denitrifiers cooperate to achieve a well-functioning denitrification system as they can utilize the nitrate intrinsically produced by the anammox reaction. This network may provide a niche for the proliferation of archaea. Hydrogenotrophic methananogens, which scavenge the key fermentation product H2, were the most abundant archaea detected. Cells resembling the polygon-shaped denitrifying methanotroph Candidatus Methylomirabilis oxyfera were observed by electron microscopy. It is hypothesized that the anammox process in a full-scale reactor triggers various reactions overall leading to efficient denitrification and a sink of carbon as biomass in anammox granules.
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Affiliation(s)
- Graciela Gonzalez-Gil
- Water Desalination and Reuse Center, Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia,
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3
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Abstract
Anaerobic ammonium-oxidizing (anammox) bacteria defy many microbiological concepts and share numerous properties with both eukaryotes and archaea. Among their most intriguing characteristics are their compartmentalized cell plan and archaeon-like cell wall. Here we review our current knowledge about anammox cell biology. The anammox cell is divided into three separate compartments by bilayer membranes. The anammox cell consists of (from outside to inside) the cell wall, paryphoplasm, riboplasm, and anammoxosome. Not much is known about the composition or function of both the anammox cell wall and the paryphoplasm compartment. The cell wall is proposed to be proteinaceous and to lack both peptidoglycan and an outer membrane typical of Gram-negative bacteria. The function of the paryphoplasm is unknown, but it contains the cell division ring. The riboplasm resembles the standard cytoplasmic compartment of other bacteria; it contains ribosomes and the nucleoid. The anammoxosome occupies most of the cell volume and is a so-called "prokaryotic organelle" analogous to the eukaryotic mitochondrion. This is the site where the anammox reaction takes place, coupled over the curved anammoxosome membrane, possibly giving rise to a proton motive force and subsequent ATP synthesis. With these unique properties, anammox bacteria are food for thought concerning the early evolution of the domains Bacteria, Archaea, and Eukarya.
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Affiliation(s)
- Laura van Niftrik
- Department of Microbiology, Institute for Water & Wetland Research, Faculty of Science, Radboud University Nijmegen, The Netherlands.
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4
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Abstract
Macro- and micro-structures of granules, developed in an upflow anaerobic acid reactor, were examined by light and electron microscopy. Every granule was found to be white, soft and non-spherical and had an open cavity at the centre. Scanning electron microscopy showed that the granules were composed of rod-shaped bacteria, of different thicknesses and lengths, arranged in three distinct layers within the granules. Transmission electron microscopic analysis of ultra-thin sections of granules, stained with Ruthenium Red, revealed the presence of extra-cellular polymeric materials around the cells. Gram staining tests confirmed the presence of both Gram-positive and Gram-negative bacteria in the granules. The intertwined nature of the bacterial arrangement in the granules and the extracellular polymeric substance that encapsulated the cell colonies contributed to the structural stability of the granules.
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Affiliation(s)
- Debraj Bhattacharyya
- Department of Civil Engineering, University of New Brunswick, Fredericton, Canada.
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5
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Duan X, Zhou J, Qiao S, Wei H. Application of low intensity ultrasound to enhance the activity of anammox microbial consortium for nitrogen removal. Bioresour Technol 2011; 102:4290-4293. [PMID: 21232945 DOI: 10.1016/j.biortech.2010.12.050] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2010] [Revised: 12/12/2010] [Accepted: 12/14/2010] [Indexed: 05/30/2023]
Abstract
In this study, effect of low intensity ultrasound on the activity of anammox microbial consortium for nitrogen removal was investigated through batch experiments at the same irradiation frequency of 25 kHz. Total nitrogen removal rate increased by about 25.5% when ultrasound intensity of 0.3 w cm(-2) was applied at an optimal irradiation time of 4 min, and further experiments demonstrated that this effect could last for about 6 days. Analysis of extracellular polymeric substances indicated that the maximum increase of carbohydrate, protein and total extracellular substances was obtained on the first day after ultrasound, which was 28.8%, 30.5% and 29.7%, respectively. As the time prolonged, the production rate of extracellular carbohydrate, protein decreased gradually. Transmission electron microscopy observation demonstrated that ultrasounded cell wall of anammox microbial consortium became thinner resulting in increased release of extracellular substances. The results suggested that application of low intensity ultrasound may enhance the activity of anammox microbial consortium and ultimately the potential for nitrogen removal.
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Affiliation(s)
- Xiumei Duan
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, PR China
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6
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Cercado-Quezada B, Delia ML, Bergel A. Testing various food-industry wastes for electricity production in microbial fuel cell. Bioresour Technol 2010; 101:2748-2754. [PMID: 20034785 DOI: 10.1016/j.biortech.2009.11.076] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2009] [Revised: 11/13/2009] [Accepted: 11/17/2009] [Indexed: 05/28/2023]
Abstract
Three food-industry wastes: fermented apple juice (FAJ), wine lees and yogurt waste (YW) were evaluated in combination with two sources of inoculum, anaerobic sludge and garden compost, to produce electricity in microbial fuel cells. Preliminary potentiostatic studies suggested that YW was the best candidate, able to provide up to 250 mA/m(2) at poised potential +0.3V/SCE. Experiments conducted with two-chamber MFCs confirmed that wine lees were definitely not suitable. FAJ was not able to start an MFC by means of its endogenous microflora, while YW was. Both FAJ and YW were suitable fuels when anaerobic sludge or compost leachate was used as inoculum source. Sludge-MFCs had better performance using YW (54 mW/m(2) at 232 mA/m(2)). In contrast, compost-leachate MFCs showed higher power density with FAJ (78 mW/m(2) at 209 mA/m(2)) than with YW (37 mW/m(2) at 144 mA/m(2)) but YW gave more stable production. Under optimized operating conditions, compost-leachate MFCs fueled with YW gave up to 92 mW/m(2) at 404 mA/m(2) and 44 mW/m(2) in stable conditions.
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Affiliation(s)
- Bibiana Cercado-Quezada
- Laboratoire de Génie de Chimique, CNRS - Université de Toulouse, 4, Allée Emile Monso, P.O. Box 74233, 31430 Toulouse Cedex 4, France
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7
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Liang Z, Liu JX, Li J. Decomposition and mineralization of aquatic humic substances (AHS) in treating landfill leachate using the Anammox process. Chemosphere 2009; 74:1315-1320. [PMID: 19131090 DOI: 10.1016/j.chemosphere.2008.11.073] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2008] [Revised: 11/23/2008] [Accepted: 11/24/2008] [Indexed: 05/27/2023]
Abstract
Aquatic humic substance (AHS) in landfill leachate is resistant to biodegradation, especially in anaerobic habitats. However, we reported here for the first time that AHS was completely biodegraded with the anaerobic ammonium oxidation (Anammox) process. As a result of aromatic-ring cleavage and mineralization, carboxylic and aliphatic organics were significantly produced, the contents of chromophores such as quinoid and ketone were remarkably decreased to decolorize the leachate, and produced carbon dioxide along with increasing carbonate was clearly presented. Of the degraded AHS of 137 mg L(-1), 51 mg L(-1) was owed to the oxidation with sulfate of 76 mg L(-1) as electron acceptor, and the rest to other metabolic mechanism. Isolation and identification of heterotrophic bacteria revealed a diversified consortium comprising four facultative anaerobic species, Bacillus sp., Paenibacillus sp., Bacteroides sp. and Staphylococcus sp., without sulfate-reducing bacteria detected. Their contribution to AHS biodegradation and sulfate reduction under the special conditions with high oxidization-reduction potential and insufficient electron acceptors has not been known yet. Further work is underway to investigate their properties and respective duties in the consortium.
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Affiliation(s)
- Zhu Liang
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Science, Chinese Academy of Sciences, Beijing, PR China
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8
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Vlaeminck SE, Terada A, Carballa M, De Clippeleir H, Boon N, Smets BF, Verstraete W. Fluorescence in situ hybridization (FISH) to elucidate structure and diversity in granular biomass for the treatment of nitrogenous wastewater. Commun Agric Appl Biol Sci 2008; 73:43-47. [PMID: 18831243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Affiliation(s)
- S E Vlaeminck
- Laboratory of Microbial Ecology and Technology, Ghent University, Coupure Links 653, BE-9000 Gent, Belgium
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9
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Villanueva L, Navarrete A, Urmeneta J, Geyer R, White DC, Guerrero R. Monitoring diel variations of physiological status and bacterial diversity in an estuarine microbial mat: an integrated biomarker analysis. Microb Ecol 2007; 54:523-31. [PMID: 17347892 DOI: 10.1007/s00248-007-9224-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2007] [Revised: 01/07/2007] [Accepted: 02/01/2007] [Indexed: 05/14/2023]
Abstract
Microbial mats are highly productive microbial systems and a source of not-yet characterized microorganisms and metabolic strategies. In this article, we introduced a lipid biomarker/microbial isolation approach to detect short-term variations of microbial diversity, physiological and redox status, and also characterize lipid biomarkers from specific microbial groups that can be further monitored. Phospholipid fractions (PLFA) were examined for plasmalogens, indicative of certain anaerobes. The glycolipid fraction was processed for polyhydroxyalkanoates (PHA) and the neutral lipid fraction was used to evaluate respiratory quinone content. Data demonstrate an increase in the metabolic stress, unbalanced growth, proportion of anaerobic bacteria and respiratory rate after the maximal photosynthetic activity. Higher accumulation of polyhydroxyalkanoates at the same sampling point also suggested a situation of carbon storage by heterotrophs closely related to photosynthetic microorganisms. Besides, the characterization of lipid biomarkers (plasmalogens, sphingolipids) from specific microbial groups provided clues about the dynamics and diversity of less-characterized mat members. In this case, lipid analyses were complemented by the isolation and characterization of anaerobic spore formers and sulfate reducers to obtain insight into their affiliation and lipid composition. The results revealed that temporal shifts in lipid biomarkers are indicative of an intense change in the physiology, redox condition, and community composition along the diel cycle, and support the hypothesis that interactions between heterotrophs and primary producers play an important role in the carbon flow in microbial mats.
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Affiliation(s)
- Laura Villanueva
- Department of Microbiology, University of Barcelona, Barcelona, Spain.
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10
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Baloch MI, Akunna JC, Collier PJ. The performance of a phase separated granular bed bioreactor treating brewery wastewater. Bioresour Technol 2007; 98:1849-55. [PMID: 16949280 DOI: 10.1016/j.biortech.2006.06.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2005] [Revised: 05/11/2006] [Accepted: 06/19/2006] [Indexed: 05/11/2023]
Abstract
This study presents the performance characteristics of a plug flow phase separated anaerobic granular bed baffled reactor (GRABBR) fed with brewery wastewater at various operating conditions. The reactor achieved chemical oxygen demand (COD) removal of 93-96% with high methane production when operated at organic loading rates (OLRs) of 2.16-13.38kg COD m(-3)d(-1). The reactor configuration and microbial environment encouraged the acidogenic dominant zone to produce intermediate products suitable for degradation in the predominantly methanogenic zone. Noticeable phase separation between acidogenesis and methanogenesis mainly occurred at high OLR, involving a greater number of compartments to contribute to wastewater treatment. The highly active nature and good settling characteristics of methanogenic granular sludge offered high biomass retention and enhanced methanogenic activities within the system. The granular structure in the acidogenic dominant zone of the GRABBR was susceptible to disintegration and flotation. Methanogenic granular sludge was a multi-layered structure with Methanosaeta-like organisms dominant in the core.
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Affiliation(s)
- M I Baloch
- Wessex Water, Bristol Wastewater Treatment Works, Kings Weston Lane, Avonmouth, Bristol, BS11 0YS, UK.
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11
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Venkata Mohan S, Vijaya Bhaskar Y, Sarma PN. Biohydrogen production from chemical wastewater treatment in biofilm configured reactor operated in periodic discontinuous batch mode by selectively enriched anaerobic mixed consortia. Water Res 2007; 41:2652-64. [PMID: 17418367 DOI: 10.1016/j.watres.2007.02.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2006] [Revised: 02/05/2007] [Accepted: 02/12/2007] [Indexed: 05/14/2023]
Abstract
Molecular hydrogen (H(2)) production with simultaneous wastewater treatment was studied in biofilm configured periodic discontinuous/sequencing batch reactor using chemical wastewater as substrate. Anaerobic mixed consortia was sequentially pretreated with repeated heat-shock (100 degrees C; 2 h) and acid (pH-3.0; 24 h) treatment procedures to selectively enrich the H(2) producing mixed consortia prior to inoculation of the reactor. The bioreactor was operated at mesophilic (room) temperature (28+/-2 degrees C) under acidophilic conditions with a total cycle period of 24 h consisting of FILL (15 min), REACT (23 h), SETTLE (30 min) and DECANT (15 min) phases. Reactor was initially operated with synthetic wastewater (SW) at OLR of 4.8 kg COD/m(3)-day and subsequently operated using composite chemical wastewater (CW) at OLR of 5.6 kg COD/m(3)-day by adjusting pH to 6.0 prior to feeding to inhibit the methanogenic activity. H(2) evolution rate differed significantly with the nature of wastewater used as substrate [SW--volumetric H(2) production rate--12.89 mmol H(2)/m(3)-min and specific H(2) production rate--0.0084 mmol H(2)/min-g COD(L) (0.026 mmol H(2)/min-g COD(R)); CW--volumetric H(2) production rate--6.076 mmol H(2)/m(3)-min and specific H(2) production rate--0.0089 mmol H(2)/min-g COD(L) (0.033 mmol H(2)/min-g COD(R))]. Relatively rapid progress towards higher H(2) yield (2 h) was observed with SW compared to the CW (10 h). Substrate (COD) reduction of 32.4% (substrate degradation rate (SDR)--1.55 kg COD/m(3)-day) and 26.7% (SDR-1.49 kg COD/m(3)-day) was observed with SW and CW, respectively. The system showed rapid stabilization tendency (SW--37 days; CW--40 days) with respect to H(2) generation and COD reduction. H(2) evolution showed relatively good correlation with VFA concentration in the case of SW (R(2)-0.961) compared to CW (R(2)-0.912). A surge in pH values from 5.87 to 4.23 (SW) and 5.93 to 4.62 (CW) was observed during the cycle operation. Integration of biofilm configuration with periodic discontinuous batch operation under the defined operating conditions showed potential to influence the microbial system by selectively enriching the specific group of microflora capable of producing H(2).
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Affiliation(s)
- S Venkata Mohan
- Indian Institute of Chemical Technology, Bioengineering and Environmental Centre, Tarnaka, Hyderabad 500007, India.
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12
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Abstract
The diversity population of microorganisms with the capability to use selenate as a terminal electron acceptor, reducing it to selenite and elemental selenium by the process known as dissimilatory selenate reduction, is largely unknown. The overall objective of this study was to gain an in-depth understanding of anaerobic biotransformation of selenium in the environment, particularly anaerobic respiration, and to characterize the microorganisms catalyzing this process. Here, we demonstrate the isolation and characterization of four novel anaerobic dissimilatory selenate-respiring bacteria enriched from a variety of sources, including sediments from three different water bodies in Chennai, India, and a tidal estuary in New Jersey. Strains S5 and S7 from India, strain KM from the Meadowlands, NJ, and strain pn1, categorized as a laboratory contaminant, were all phylogenetically distinct, belonging to various phyla in the bacterial domain. The 16S rRNA gene sequence shows that strain S5 constitutes a new genus belonging to Chrysiogenetes, while strain S7 belongs to the Deferribacteres, with greater than 98% 16S rRNA gene similarity to Geovibrio ferrireducens. Strain KM is related to Malonomonas rubra, Pelobacter acidigallici, and Desulfuromusa spp., with 96 to 97% 16S rRNA gene similarity. Strain pn1 is 99% similar to Pseudomonas stutzeri. Strains S5, S7, and KM are obligately anaerobic selenate-respiring microorganisms, while strain pn1 is facultatively anaerobic. Besides respiring selenate, all these strains also respire nitrate.
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MESH Headings
- Bacteria, Anaerobic/classification
- Bacteria, Anaerobic/isolation & purification
- Bacteria, Anaerobic/metabolism
- Bacteria, Anaerobic/ultrastructure
- Bacterial Typing Techniques
- Carbon/metabolism
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- DNA, Ribosomal/chemistry
- DNA, Ribosomal/genetics
- Fermentation
- Genes, rRNA/genetics
- Geologic Sediments/microbiology
- India
- Microscopy, Electron, Transmission
- Molecular Sequence Data
- New Jersey
- Oxidation-Reduction
- Phylogeny
- RNA, Bacterial/genetics
- RNA, Ribosomal, 16S/genetics
- Seawater/microbiology
- Selenic Acid
- Selenium Compounds/metabolism
- Sequence Analysis, DNA
- Sequence Homology, Nucleic Acid
- Sodium Selenite/metabolism
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Affiliation(s)
- Priya Narasingarao
- Department of Biochemistry and Microbiology, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA
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Chamchoi N, Nitisoravut S. Anammox enrichment from different conventional sludges. Chemosphere 2007; 66:2225-32. [PMID: 17207839 DOI: 10.1016/j.chemosphere.2006.09.036] [Citation(s) in RCA: 121] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2006] [Revised: 09/15/2006] [Accepted: 09/15/2006] [Indexed: 05/13/2023]
Abstract
Three sets of sequencing batch reactor (SBR) were used for Anammox enrichment from conventional sludges including upflow anaerobic sludge blanket, activated sludge, and anaerobic digestion sludge. After four months of operation, the Anammox activity occurred in all reactors allowing continuous removal of ammonium and nitrite. The morphology of the cultivated Anammox sludge was observed using scanning electron microscope. The photographs showed that the obtained culture was mostly spherical in shape, presumably Anammox culture. There were also filamentous-like bacteria co-existing in the system. Fluorescence in situ hybridization (FISH) analysis using 16S rRNA targeting oligonucleotide probes PLA46 and Amx820 showed that the dominant population developed in all SBRs was hybridized with both PLA46 and Amx820 gene probes. It means that the cultivated biomass in all SBRs was classified in the group of Planctomycetales bacteria with respect to the anaerobic ammonium-oxidizing bacteria, Candidatus Brocadia anammoxidans and Candidatus Kuenenia stuttgartiensis. Numerous time sequences were tested in this experiment. The shortest workable reaction time was found in the range from 5 to 7 h. Good quiescence of sludge was obtained at 30 min of settle period followed by a discharge period of 15 min. A long-term performance showed a near perfect removal of nitrite based on the influent NO2(-)-N concentration of 50-70 mg l(-1). The maximum ammonia removal efficiency was 80% with the influent NH4(+)-N concentration of 40-60 mg l(-1). It is, therefore, concluded that Anammox cultivation from conventional sludges was highly possible under control environment within four months.
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Affiliation(s)
- Nutchanat Chamchoi
- Environmental Technology Program, Sirindhorn International Institute of Technology, Thammasat University, P.O. Box 22, Thammasat Rangsit Post Office, Pathumthani 12121, Thailand
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14
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Kartal B, Rattray J, van Niftrik LA, van de Vossenberg J, Schmid MC, Webb RI, Schouten S, Fuerst JA, Damsté JS, Jetten MSM, Strous M. Candidatus “Anammoxoglobus propionicus” a new propionate oxidizing species of anaerobic ammonium oxidizing bacteria. Syst Appl Microbiol 2007; 30:39-49. [PMID: 16644170 DOI: 10.1016/j.syapm.2006.03.004] [Citation(s) in RCA: 360] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2006] [Indexed: 10/24/2022]
Abstract
The bacteria that mediate the anaerobic oxidation of ammonium (anammox) are detected worldwide in natural and man-made ecosystems, and contribute up to 50% to the loss of inorganic nitrogen in the oceans. Two different anammox species rarely live in a single habitat, suggesting that each species has a defined but yet unknown niche. Here we describe a new anaerobic ammonium oxidizing bacterium with a defined niche: the co-oxidation of propionate and ammonium. The new anammox species was enriched in a laboratory scale bioreactor in the presence of ammonium and propionate. Interestingly, this particular anammox species could out-compete other anammox bacteria and heterotrophic denitrifiers for the oxidation of propionate in the presence of ammonium, nitrite and nitrate. We provisionally named the new species Candidatus "Anammoxoglobus propionicus".
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Affiliation(s)
- Boran Kartal
- Department of Microbiology, Institute for Water and Wetland Research, Radboud University Nijmegen, Nijmegen 6525 ED, Netherlands
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15
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Zhou W, Imai T, Ukita M, Li F, Yuasa A. Effect of limited aeration on the anaerobic treatment of evaporator condensate from a sulfite pulp mill. Chemosphere 2007; 66:924-9. [PMID: 16844188 DOI: 10.1016/j.chemosphere.2006.06.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2005] [Revised: 06/03/2006] [Accepted: 06/06/2006] [Indexed: 05/10/2023]
Abstract
Serious inhibition was found in the regular up-flow anaerobic sludge blanket (UASB) reactor in treating the evaporator condensate from a sulfite pulp mill, which contained high strength sulfur compounds. After applying the direct limited aeration in the UASB, the inhibition was alleviated gradually and the activity of the microorganisms was recovered. The COD removal rate increased from 40% to 80% at the organic loading rate of 8kgCODm(-3)d(-1) and a hydraulic retention time of 12h. Limited aeration caused no oxygen inhibition to the anaerobic microorganisms but instigated sulfide oxidization and H(2)S removal, which was beneficial to the methanogens. The experiment confirmed the feasibility of applying limited aeration in the anaerobic reactor to alleviate the sulfide inhibition. It also proved that the anaerobic system was actually aerotolerant. SEM observation showed that the predominant microorganisms partly changed from rod-shaped methanogens to cocci after the UASB reactor was aerated.
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Affiliation(s)
- Weili Zhou
- River Basin Research Centre, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.
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Pason P, Kyu KL, Ratanakhanokchai K. Paenibacillus curdlanolyticus strain B-6 xylanolytic-cellulolytic enzyme system that degrades insoluble polysaccharides. Appl Environ Microbiol 2006; 72:2483-90. [PMID: 16597947 PMCID: PMC1448999 DOI: 10.1128/aem.72.4.2483-2490.2006] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A facultatively anaerobic bacterium, Paenibacillus curdlanolyticus B-6, isolated from an anaerobic digester produces an extracellular xylanolytic-cellulolytic enzyme system containing xylanase, beta-xylosidase, arabinofuranosidase, acetyl esterase, mannanase, carboxymethyl cellulase (CMCase), avicelase, cellobiohydrolase, beta-glucosidase, amylase, and chitinase when grown on xylan under aerobic conditions. During growth on xylan, the bacterial cells were found to adhere to xylan from the early exponential growth phase to the late stationary growth phase. Scanning electron microscopic analysis revealed the adhesion of cells to xylan. The crude enzyme preparation was found to be capable of binding to insoluble xylan and Avicel. The xylanolytic-cellulolytic enzyme system efficiently hydrolyzed insoluble xylan, Avicel, and corn hulls to soluble sugars that were exclusively xylose and glucose. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of a crude enzyme preparation exhibited at least 17 proteins, and zymograms revealed multiple xylanases and cellulases containing 12 xylanases and 9 CMCases. The cellulose-binding proteins, which are mainly in a multienzyme complex, were isolated from the crude enzyme preparation by affinity purification on cellulose. This showed nine proteins by SDS-PAGE and eight xylanases and six CMCases on zymograms. Sephacryl S-300 gel filtration showed that the cellulose-binding proteins consisted of two multienzyme complexes with molecular masses of 1,450 and 400 kDa. The results indicated that the xylanolytic-cellulolytic enzyme system of this bacterium exists as multienzyme complexes.
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Affiliation(s)
- Patthra Pason
- School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, Bangkok 10140, Thailand
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17
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Silva AJ, Hirasawa JS, Varesche MB, Foresti E, Zaiat M. Evaluation of support materials for the immobilization of sulfate-reducing bacteria and methanogenic archaea. Anaerobe 2006; 12:93-8. [PMID: 16701621 DOI: 10.1016/j.anaerobe.2005.12.003] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2005] [Revised: 12/01/2005] [Accepted: 12/11/2005] [Indexed: 11/29/2022]
Abstract
This paper reports on the adhesion of sulfate-reducing bacteria (SRB) and methanogenic archaea on polyurethane foam (PU), vegetal carbon (VC), low-density polyethylene (PE) and alumina-based ceramics (CE). Anaerobic differential reactors fed with a sulfate-rich synthetic wastewater were used to evaluate the formation of a biofilm. The PU presented the highest specific biomass concentration throughout the experiment, achieving 872 mg TVS/g support, while 84 mg TVS/g support was the maximum value obtained for the other materials. FISH results showed that bacterial cells rather than archaeal cells were predominant on the biofilms. These cells, detected with EUB338 probe, accounted for 76.2% (+/-1.6%), 79.7% (+/-1.3%), 84.4% (+/-1.4%) and 60.2% (+/-1.0%) in PU, VC, PE and CE, respectively, of the 4'6-diamidino-2-phenylindole (DAPI)-stained cells. From these percentages, 44.8% (+/-2.1%), 55.4% (+/-1.2%), 32.7% (+/-1.4%) and 18.1% (+/-1.1%), respectively, represented the SRB group. Archaeal cells, detected with ARC915 probe, accounted for 33.1% (+/-1.6%), 25.4% (+/-1.3%), 22.6% (+/-1.1%) and 41.9% (+/-1.0%) in PU, VC, PE and CE, respectively, of the DAPI-stained cells. Sulfate reduction efficiencies of 39% and 45% and mean chemical oxygen demand (COD) removal efficiencies of 86% and 90% were achieved for PU and VC, respectively. The other two supports, PE and CE, provided mean COD removal efficiencies of 84% and 86%, respectively. However, no sulfate reduction was observed with these supports.
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Affiliation(s)
- A J Silva
- Universidade de São Paulo (USP), Escola de Engenharia de São Carlos (EESC), Departamento de Hidráulica e Saneamento, Laboratório de Processos Biológicos, Av. Trabalhador São-carlense, 400, CEP: 12560-250 São Carlos, SP, Brazil
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18
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Abstract
The abundant microbial population in a 3,043-m-deep Greenland glacier ice core was dominated by ultrasmall cells (<0.1 microm3) that may represent intrinsically small organisms or starved, minute forms of normal-sized microbes. In order to examine their diversity and obtain isolates, we enriched for ultrasmall psychrophiles by filtering melted ice through filters with different pore sizes, inoculating anaerobic low-nutrient liquid media, and performing successive rounds of filtrations and recultivations at 5 degrees C. Melted ice filtrates, cultures, and isolates were analyzed by scanning electron microscopy, flow cytometry, cultivation, and molecular methods. The results confirmed that numerous cells passed through 0.4-microm, 0.2-microm, and even 0.1-microm filters. Interestingly, filtration increased cell culturability from the melted ice, yielding many isolates related to high-G+C gram-positive bacteria. Comparisons between parallel filtered and nonfiltered cultures showed that (i) the proportion of 0.2-microm-filterable cells was higher in the filtered cultures after short incubations but this difference diminished after several months, (ii) more isolates were obtained from filtered (1,290 isolates) than from nonfiltered (447 isolates) cultures, and (iii) the filtration and liquid medium cultivation increased isolate diversity (Proteobacteria; Cytophaga-Flavobacteria-Bacteroides; high-G+C gram-positive; and spore-forming, low-G+C gram-positive bacteria). Many isolates maintained their small cell sizes after recultivation and were phylogenetically novel or related to other ultramicrobacteria. Our filtration-cultivation procedure, combined with long incubations, enriched for novel ultrasmall-cell isolates, which is useful for studies of their metabolic properties and mechanisms for long-term survival under extreme conditions.
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MESH Headings
- Bacteria/classification
- Bacteria/isolation & purification
- Bacteria/ultrastructure
- Bacteria, Anaerobic/classification
- Bacteria, Anaerobic/genetics
- Bacteria, Anaerobic/isolation & purification
- Bacteria, Anaerobic/ultrastructure
- Cell Size
- Cold Climate
- DNA, Bacterial/isolation & purification
- DNA, Ribosomal/genetics
- Ecosystem
- Filtration/methods
- Flow Cytometry
- Genome, Bacterial
- Greenland
- Ice/analysis
- Microscopy, Electron, Scanning
- Molecular Sequence Data
- Phylogeny
- RNA, Bacterial/genetics
- RNA, Ribosomal, 16S/genetics
- Water Microbiology
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Affiliation(s)
- Vanya I Miteva
- Department of Biochemistry and Molecular Biology, 211 S. Frear, The Pennsylvania State University, University Park, PA 16802, USA.
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19
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Abstract
Recent progress in microbiology resulted in the enrichment and isolation of anaerobic bacteria capable of the biodegradation of various hydrocarbons under a variety of electron-accepting conditions. Problems challenging the enrichment and isolation of anaerobic hydrocarbonclastic organisms required new approaches and modifications of conventional microbiological techniques. This chapter summarizes the collective experience accumulated in this area starting from anaerobic sampling precautions and includes all stages of cultivation from the construction of initial incubations to final isolation steps and the evaluation of culture purity.
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Affiliation(s)
- Irene A Davidova
- Department of Microbiology, University of Oklahoma, Norman 73019, USA
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20
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Abstract
Intrauterine devices (IUDs) are highly effective, long-term methods of contraception; however, IUD use is limited due to concerns about an increased risk of pelvic inflammatory disease (PID) and subsequent complications. A retrospective review of clinical and microbiological data of 127 participants was carried out over a 3 year period. IUDs were removed and sent for microbiological examination. A 10 year old IUD, removed because of the symptoms of PID, was investigated via both microbial culture and scanning electron microscopy. The primary objective of this study was to examine the bacteria present on removed IUDs after different times in situ by using aerobic and anaerobic culture methods. A close association of the distribution of aerobic and anaerobic bacteria on the IUDs with different times in situ was found.
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Affiliation(s)
- Z Pál
- Department of Obstetrics and Gynaecology1 and Institute of Clinical Microbiology2, Faculty of Medicine, University of Szeged, Szeged H-6701, PO Box 427, Hungary 3Institute of Medical Microbiology, Martin Luther University, Halle-Wittenberg, Germany
| | - E Urbán
- Department of Obstetrics and Gynaecology1 and Institute of Clinical Microbiology2, Faculty of Medicine, University of Szeged, Szeged H-6701, PO Box 427, Hungary 3Institute of Medical Microbiology, Martin Luther University, Halle-Wittenberg, Germany
| | - E Dósa
- Department of Obstetrics and Gynaecology1 and Institute of Clinical Microbiology2, Faculty of Medicine, University of Szeged, Szeged H-6701, PO Box 427, Hungary 3Institute of Medical Microbiology, Martin Luther University, Halle-Wittenberg, Germany
| | - A Pál
- Department of Obstetrics and Gynaecology1 and Institute of Clinical Microbiology2, Faculty of Medicine, University of Szeged, Szeged H-6701, PO Box 427, Hungary 3Institute of Medical Microbiology, Martin Luther University, Halle-Wittenberg, Germany
| | - E Nagy
- Department of Obstetrics and Gynaecology1 and Institute of Clinical Microbiology2, Faculty of Medicine, University of Szeged, Szeged H-6701, PO Box 427, Hungary 3Institute of Medical Microbiology, Martin Luther University, Halle-Wittenberg, Germany
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21
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Chu CP, Tsai DG, Lee DJ, Tay JH. Size-dependent anaerobic digestion rates of flocculated activated sludge: role of intrafloc mass transfer resistance. J Environ Manage 2005; 76:239-44. [PMID: 15932786 DOI: 10.1016/j.jenvman.2005.01.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2004] [Revised: 11/20/2004] [Accepted: 01/21/2005] [Indexed: 05/02/2023]
Abstract
The anaerobic digestion rate for flocculated sludge has been considered to be lower than that of original sludge, particularly in the later stages of digestion; attributed this relatively slower rate to the increased mass transfer resistance for reactants through the large flocs after flocculation. This study confirmed that methane production was retarded by flocculation. The structure of the floc was identified with fluorescence in situ hybridization (FISH) and a confocal laser scanning microscope (CLSM) technique. To verify the mass transfer resistance induced by flocculation, microsensors were applied to assess the response of oxygen concentration distribution inside the flocs that are subjected to sudden changes in ambient oxygen levels. Response time for the electrode at a floc's center was five times greater than the response time in original sludge flocs. Although the effective diffusivity of oxygen in the floc increased by 2.3 times after flocculation, the increased size of the flocculated floc was the major contributor to the total mass transfer resistance to oxygen.
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Affiliation(s)
- C P Chu
- Chemical Engineering Department, National Taiwan University, Taipei 106, Taiwan, ROC
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22
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Buzzini AP, Gianotti EP, Pires EC. UASB performance for bleached and unbleached kraft pulp synthetic wastewater treatment. Chemosphere 2005; 59:55-61. [PMID: 15698644 DOI: 10.1016/j.chemosphere.2004.09.102] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2004] [Revised: 09/22/2004] [Accepted: 09/30/2004] [Indexed: 05/24/2023]
Abstract
This paper presents the performance of two bench scale Upflow Anaerobic Sludge Blanket reactors (UASB) used for the treatment of synthetic substrates that simulate bleached and unbleached cellulose pulp plant wastewaters. The control reactor was fed with diluted black liquor and the treatment reactor with the same substrate plus a mixture of chlorinated organics. The total concentration of the chlorinated compounds was gradually increased from 2.5 mg l-1 to 15.0 mg l-1. The average COD removal efficiency during the last phase of the experiment was 81% in the control reactor and 76% in the treatment reactor. These results indicate the capability of UASB reactors to treat this kind of wastewater and the low impact of the chlorinated organics on COD removal efficiency. The minimum overall chlorinated organics removal efficiency was 71% and the maximum was 99.7%. The experiment indicates that under the conditions used in this research the presence of chlorinated organics does not negatively impact the treatment process.
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Affiliation(s)
- A P Buzzini
- Department of Hydraulics and Sanitation, School of Engineering of São Carlos, University of São Paulo-EESC, Av. Trabalhador São-carlense 400, CEP: 13566-590 São Carlos, SP, Brazil
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23
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O'Reilly C, Colleran E. Microbial sulphate reduction during anaerobic digestion: EGSB process performance and potential for nitrite suppression of SRB activity. Water Sci Technol 2005; 52:371-6. [PMID: 16180452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The present study investigated mesophilic anaerobic treatment of sulphate-containing wastewater in EGSB reactors and assessed the inclusion of nitrite in the reactor influent as a method for control of biological sulphate reduction. Two EGSB reactors, R1 and R2, were operated for a period of 581 days at varying volumetric loading rates, COD/SO4(2-) ratios and influent nitrite concentrations (R2 only). COD removal efficiencies of > 93% were achieved in both reactors at influent sulphate concentrations of up to 3,000 mg l(-1). A two-fold increase in the influent sulphate concentration, giving an influent COD/SO4(2-) ratio of 2, resulted in a reduction in reactor COD removal efficiency to 84% and 89%, in R1 and R2, respectively. Despite inclusion of nitrite in the R2 influent at concentrations up to 500 mg NO2-N l(-1), sulphate reduction proceeded similarly in R2 and R1, suggesting the ineffectiveness of nitrite as a potential inhibitor of SRB
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Affiliation(s)
- C O'Reilly
- Environmental Microbiology Research Unit, Department of Microbiology, National University of Ireland, Galway, Ireland.
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24
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Bardiya N, Bae JH. Bioremediation potential of a perchlorate-enriched sewage sludge consortium. Chemosphere 2005; 58:83-90. [PMID: 15522336 DOI: 10.1016/j.chemosphere.2004.09.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2003] [Revised: 05/19/2004] [Accepted: 09/02/2004] [Indexed: 05/24/2023]
Abstract
The purpose of this work was to explore the reductive bioremediation potential of a perchlorate-enriched facultative anaerobic consortium. Rapid perchlorate reduction and bacterial growth were observed up to 1.84 g l(-1) of perchlorate, but not at 3.82 g l(-1) due to the toxicity. The specific growth rate of the mixed consortium was 0.1 h(-1). The consortium co-reduced perchlorate and nitrate with acetate as e- donor and carbon source. The presence of nitrate slowed down the perchlorate reduction rate. The other e- acceptors utilized include oxygen, chlorate, Cr(VI), and selenate. Over 95% of the 16 mg l(-1) of added Cr(VI) was reduced within 24 h of incubation with a high-density perchlorate-grown consortium. However, the consortium failed to couple growth with reduction of nitrite, sulfate, thiosulfate, and sulfite. During the search for autotrophic perchlorate reduction, many consortia from very diverse natural sources could not use sulfur compounds such as thiosulfate as e- donor.
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Affiliation(s)
- Nirmala Bardiya
- Department of Civil and Environmental Engineering and Geosystem Engineering, Inha University, 253 Yonghyun-Dong, Nam-Gu, Inchon 402-751, South Korea
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25
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Ye Q, Roh Y, Carroll SL, Blair B, Zhou J, Zhang CL, Fields MW. Alkaline anaerobic respiration: isolation and characterization of a novel alkaliphilic and metal-reducing bacterium. Appl Environ Microbiol 2004; 70:5595-602. [PMID: 15345448 PMCID: PMC520920 DOI: 10.1128/aem.70.9.5595-5602.2004] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Iron-reducing enrichments were obtained from leachate ponds at the U.S. Borax Company in Boron, Calif. Based on partial small-subunit (SSU) rRNA gene sequences (approximately 500 nucleotides), six isolates shared 98.9% nucleotide identity. As a representative, the isolate QYMF was selected for further analysis. QYMF could be grown with Fe(III)-citrate, Fe(III)-EDTA, Co(III)-EDTA, or Cr(VI) as electron acceptors, and yeast extract and lactate could serve as electron donors. Growth during iron reduction occurred over the pH range of 7.5 to 11.0 (optimum, pH 9.5), a sodium chloride range of 0 to 80 g/liter (optimum, 20 g/liter), and a temperature range of 4 to 45 degrees C (optimum, approximately 35 degrees C), and iron precipitates were formed. QYMF was a strict anaerobe that could be grown in the presence of borax, and the cells were straight rods that produced endospores. Sodium chloride and yeast extract stimulated growth. Phylogenetic analysis of the SSU rRNA gene indicated that the bacterium was a low-G+C gram-positive microorganism and had 96 and 92% nucleotide identity with Alkaliphilus transvaalensis and Alkaliphilus crotonatoxidans, respectively. The major phospholipid fatty acids were 14:1, 16:1omega7c, and 16:0, which were different from those of other alkaliphiles but similar to those of reported iron-reducing bacteria. The results demonstrated that the isolate might represent a novel metal-reducing alkaliphilic species. The name Alkaliphilus metalliredigens sp. nov. is proposed. The isolation and activity of metal-reducing bacteria from borax-contaminated leachate ponds suggest that bioremediation of metal-contaminated alkaline environments may be feasible and have implications for alkaline anaerobic respiration.
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Affiliation(s)
- Qi Ye
- Department of Geology, University of Missouri, Columbia, MO, USA
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26
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Rao AG, Naidu GV, Prasad KK, Rao NC, Mohan SV, Jetty A, Sarma PN. Anaerobic treatment of wastewater with high suspended solids from a bulk drug industry using fixed film reactor (AFFR). Bioresour Technol 2004; 93:241-247. [PMID: 15062818 DOI: 10.1016/j.biortech.2003.11.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2003] [Revised: 10/04/2003] [Accepted: 11/03/2003] [Indexed: 05/24/2023]
Abstract
Studies are carried out on the treatment of wastewater from a bulk drug industry using an anaerobic fixed film reactor (AFFR) designed and fabricated in the laboratory. The chemical oxygen demand (COD) and total dissolved solids (TDS) of the wastewater are found to be very high with low Biochemical oxygen demand (BOD) to COD ratio and high total suspended solid (TSS) concentration. Acclimatization of seed consortia and start up of the reactor is carried out by directly using the wastewater, which resulted in reducing the period of startup to 30 days. The reactor is studied at different organic loading rates (OLR) and it is found that the optimum OLR is 10 kg COD/m3/day. The wastewater under investigation, which is having considerable quantity of SS, is treated anaerobically without any pretreatment. The COD and BOD of the reactor outlet wastewater are monitored and reduction at steady state and optimum OLR is observed to be 60-70% of COD and 80-90% of BOD. The reactor is subjected to organic shock loads at two different OLR and it is observed that the reactor could withstand shocks and performance could be restored to normalcy at that OLR. The results obtained indicated that AFFR could be used efficiently for the treatment of wastewater from a bulk drug industry having high COD, TDS and TSS.
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Affiliation(s)
- A Gangagni Rao
- Biochemical and Environmental Engineering Centre, Indian Institute of Chemical Technology, Hyderabad 500 007, India
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27
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Abstract
OBJECTIVE The purpose of the present study was to reexamine the possibility that bacteria, particularly anaerobes, are present in aortic aneurysms. METHODS From December 2000 to November 2001, 53 samples from aneurysm walls were collected from 49 patients during reconstructive surgery. The tissue specimens were sectioned and cultured under anaerobic conditions. Twenty-eight specimens were also subjected to scanning or transmission electron microscopy. RESULTS Anaerobic cultivation yielded bacteria in 14 of the 53 samples (26.4%). All bacteria were gram-positive cocci or rods from nine genera and 12 species. Five cultures (35%) were mixed, containing two bacterial species. Mixed aerobic and anaerobic species were found in four samples (28.5%). Anaerobic bacteria were recovered from 10 of 14 positive cultures (71%). Among anaerobes found were Propionibacterium acnes, Propionibacterium granulosum, Actinomyces viscosus, Actinomyces naeslundii, and Eggerthella lenta. Coaggregating bacteria of different sizes and structure were found on the aneurysm walls and inside the intravascular plaque at electron microscopy. Bacteria were found in 20 of the 28 samples (71%) examined with scanning or transmission electron microscopy. CONCLUSION Multiple bacteria, many of which did not belong to the indigenous skin microflora, colonize aortic aneurysms. It is not clear whether the bacteria contribute to weakening of the aortic wall by eliciting inflammation or whether they are secondary colonizers of aneurysms.
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Affiliation(s)
- Rafael Marques da Silva
- Institute of Oral Biology, Faculty of Dentistry, University of Oslo, PO Box 1052 Blindern, N-0316 Oslo, Norway.
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He J, Ritalahti KM, Yang KL, Koenigsberg SS, Löffler FE. Detoxification of vinyl chloride to ethene coupled to growth of an anaerobic bacterium. Nature 2003; 424:62-5. [PMID: 12840758 DOI: 10.1038/nature01717] [Citation(s) in RCA: 313] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2003] [Accepted: 04/29/2003] [Indexed: 11/09/2022]
Abstract
Tetrachloroethene (PCE) and trichloroethene (TCE) are ideal solvents for numerous applications, and their widespread use makes them prominent groundwater pollutants. Even more troubling, natural biotic and abiotic processes acting on these solvents lead to the accumulation of toxic intermediates (such as dichloroethenes) and carcinogenic intermediates (such as vinyl chloride). Vinyl chloride was found in at least 496 of the 1,430 National Priorities List sites identified by the US Environmental Protection Agency, and its precursors PCE and TCE are present in at least 771 and 852 of these sites, respectively. Here we describe an unusual, strictly anaerobic bacterium that destroys dichloroethenes and vinyl chloride as part of its energy metabolism, generating environmentally benign products (biomass, ethene and inorganic chloride). This organism might be useful for cleaning contaminated subsurface environments and restoring drinking-water reservoirs.
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Affiliation(s)
- Jianzhong He
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0512, USA
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29
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Abstract
Efforts were made to assess the efficiency of an anaerobic filter packed with porous floating ceramic media and to identify the optimum operational condition of anaerobic filter as a pretreatment of swine wastewater for the subsequent biological removal of nitrogen and phosphorus. A stepwise decrease in hydraulic retention time (HRT) and an increase in organic loading rate (OLR) were utilized in an anaerobic filter reactor at mesophilic temperature (35 degrees C). The optimum operating condition of the anaerobic filter was found to be at an HRT of 1 d. A soluble chemical oxygen demand (COD) removal efficiency of 62% and a total suspended solids removal efficiency of 39% at an HRT of 1 d were achieved with an OLR of 16.0 kg total COD/(m3.d), respectively. The maximum methane production rate approached 1.70 vol of biogas produced per volume of reactor per day at an HRT of 1 d. It was likely that the effluent COD/total Kjeldahl nitrogen ratio of 22, the COD/total phosphorous ratio of 47, and the high effluent alkalinity >2500 mg/L as CaCO3 of the anaerobic filter operated at an HRT of 1 d was adequate for the subsequent biological removal of nitrogen and phosphorus.
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Affiliation(s)
- Ho Kang
- Department of Environmental Engineering, Chungnam National University, 220 Goongdong, Yuseonggu, Daejeon 305-764, Korea.
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30
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Araujo JC, Téran FC, Oliveira RA, Nour EAA, Montenegro MAP, Campos JR, Vazoller RF. Comparison of hexamethyldisilazane and critical point drying treatments for SEM analysis of anaerobic biofilms and granular sludge. J Electron Microsc (Tokyo) 2003; 52:429-433. [PMID: 14599106 DOI: 10.1093/jmicro/52.4.429] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We present a fast procedure for scanning electron microscopy (SEM) analysis in which hexamethyldisilazane (HMDS) solvent, instead of the critical point drying, is used to remove liquids from a microbiological specimen. The results indicate that the HMDS solvent is suitable for drying samples of anaerobic cells for examination by SEM and does not cause cell structure disruption.
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Affiliation(s)
- Juliana C Araujo
- Departamento de Hidráulica e Saneamento, Universidade de São Paulo, Escola de Engenharia de São Carlos, Av. Trabalhador São Carlense 400, São Carlos-SP, 13566-590, Brazil.
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31
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Medvetskiĭ EB, Kryzhevskiĭ VV, Bondarchuk OI, Litvinenko AN. [Effect of spore-free anaerobic microorganisms of pancreatic tissue in experimental acute pancreatitis]. Klin Khir 2002:57-9. [PMID: 12440216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
Abstract
The simulation model of an acute pancreatitis (AP), using translocation of microorganisms from intestine to ductal system and pancreatic tissue, was created in experiment on dogs. Interrelationships between pancreatic tissue and anaerobic microorganism in an AP were studied, using electron microscopy. Possibility of the microorganisms migration to pancreas from ductal system in early stage of AP due to enhanced reproduction of anaerobic microorganisms in duodenum was established. It is impossible to exclude the possibility of their invasion via the lymph and the blood flow into destructively changed pancreatic tissue in late terms of the disease.
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Shin HS, Han SK, Song YC, Lee CY. Performance of UASB reactor treating leachate from acidogenic fermenter in the two-phase anaerobic digestion of food waste. Water Res 2001; 35:3441-3447. [PMID: 11547866 DOI: 10.1016/s0043-1354(01)00041-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This study was conducted to investigate the performance of the upflow anaerobic sludge blanket (UASB) reactor treating leachate from acidogenic fermenter in the two-phase anaerobic digestion of food waste. The chemical oxygen demand (COD) removal efficiency was consistently over 96% up to the loading rates of 15.8 g COD/l d. The methane production rate increased to 5.51/l d. Of all the COD removed, 92% was converted to methane and the remaining presumably to biomass. At loading rates over 18.7 g COD/l d, the COD removal efficiency decreased due to sludge flotation and washout in the reactor, which resulted from short HRT of less than 10.6 h. The residual propionate concentration was the highest among the volatile fatty acids (VFA) in the effluent. The specific methanogenic activity (SMA) analysis showed that the VFA-degrading activity of granule was the highest for butyrate, and the lowest for propionate. Typical granules were found to be mainly composed of microcolonies of Methanosaeta. The size distribution of sludge particles indicated that partially granulated sludge could maintain the original structure of granular sludge and continue to gain size in the UASB reactor treating leachate from acidogenic fermenter.
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Affiliation(s)
- H S Shin
- Department of Civil Engineering, Korea Advanced Institute of Science and Technology, Taejon, South Korea.
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Margulis L, Olendzenski L, Afzelius BA. Endospore-forming filamentous bacteria symbiotic in termites: ultrastructure and growth in culture of Arthromitus. Symbiosis 2001; 8:95-116. [PMID: 11539024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Many morphologically distinguishable filamentous spore-forming bacteria symbiotic in the paunch (hypertrophied hindguts) of wood-eating insects have been seen since Arthromitus was first described and named as a plant by Leidy in 1850. Previous descriptions were inadequate for acceptance of the group in modern bacteriological literature. Twenty-two distinguishable arthromitids in nine different arthropod hosts are recorded on the basis of microscopic studies. Five are named, including two whose ultrastructure are detailed: Arthromitus chasei sp. nov. that lives in the damp wood-eating termite Zootermopsis angusticollis (from the west coast of North America) and Arthromitus reticulitermitidis sp. nov. from the subterranean west coast termite Reticulitermes tibialis. A pterotermiditis from the desert termite Pterotermitidis occidentis; A. zootermopsidis, also from Z. angusticollis; and A. cristatus (Leidy, 1881) from Reticulitermes flavipes of eastern North America are also named here. Characterized by trichomes that show a morphogenetic sequence from no spores through immature spores to mature spores with spore filaments, Arthromitus symbionts can be identified as members of the genus by light microscopy and habitat. Electron microscopy reveals their remarkable complexity. They attach by spore filaments to various objects including the host gut wall; their maturation extends distally toward the termite lumen. By surface sterilization of the termite, maceration of the paunch, exposure to boiling temperatures and plating on soft acetate agar, the heat resistant nature of the spores and facultatively aerobic nature of Arthromitus sp. (from Zootermopsis) was demonstrated.
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Affiliation(s)
- L Margulis
- Botany Department, University of Massachusetts, Amherst 01003, USA
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Wery N, Moricet JM, Cueff V, Jean J, Pignet P, Lesongeur F, Cambon-Bonavita MA, Barbier G. Caloranaerobacter azorensis gen. nov., sp. nov., an anaerobic thermophilic bacterium isolated from a deep-sea hydrothermal vent. Int J Syst Evol Microbiol 2001; 51:1789-1796. [PMID: 11594610 DOI: 10.1099/00207713-51-5-1789] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A thermophilic, anaerobic, chemo-organotrophic bacterium, designated MV1087T, was isolated from a deep-sea hydrothermal chimney sample collected from the Mid-Atlantic Ridge. The cells were straight, motile and stained gram-negative. Growth was observed from 45 to 65 degrees C, with an optimum around 65 degrees C. No growth was observed at 40 or 70 degrees C. Growth was observed from pH 5.5 to 9.0 and the optimum pH was around 7. The salinity range for growth was 10-100 g sea salt l(-1) (corresponding to 6.5-65 g NaCl l(-1)) with an optimum at 30 g sea salt l(-1) (20 g NaCl l(-1)). Strain MV1087T was heterotrophic, able to ferment proteinaceous substrates, such as brain/heart infusion and gluten, and carbohydrates, such as glucose, xylan and starch. The DNA G+C content was 27 mol%. Phylogenetic analyses using 16S rDNA sequences indicated that strain MV1087T belonged to cluster XII of the Clostridium subphylum. Due to its phenotypic and genotypic characteristics, isolate MV1087T is proposed as a novel species of a new genus, Caloranaerobacter azorensis gen. nov., sp. nov. The type strain is MV1087T (= CNCM I-2543T = DSM 13643T).
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Eder W, Jahnke LL, Schmidt M, Huber R. Microbial diversity of the brine-seawater interface of the Kebrit Deep, Red Sea, studied via 16S rRNA gene sequences and cultivation methods. Appl Environ Microbiol 2001; 67:3077-85. [PMID: 11425725 PMCID: PMC92984 DOI: 10.1128/aem.67.7.3077-3085.2001] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The brine-seawater interface of the Kebrit Deep, northern Red Sea, was investigated for the presence of microorganisms using phylogenetic analysis combined with cultivation methods. Under strictly anaerobic culture conditions, novel halophiles were isolated. The new rod-shaped isolates belong to the halophilic genus Halanaerobium and are the first representatives of the genus obtained from deep-sea, anaerobic brine pools. Within the genus Halanaerobium, they represent new species which grow chemoorganotrophically at NaCl concentrations ranging from 5 to 34%. The cellular fatty acid compositions are consistent with those of other Halanaerobium representatives, showing unusually large amounts of Delta7 and Delta11 16:1 fatty acids. Phylogenetic analysis of the brine-seawater interface sample revealed the presence of various bacterial 16S rRNA gene sequences dominated by cultivated members of the bacterial domain, with the majority affiliated with the genus Halanaerobium. The new Halanaerobium 16S rRNA clone sequences showed the highest similarity (99.9%) to the sequence of isolate KT-8-13 from the Kebrit Deep brine. In this initial survey, our polyphasic approach demonstrates that novel halophiles thrive in the anaerobic, deep-sea brine pool of the Kebrit Deep, Red Sea. They may contribute significantly to the anaerobic degradation of organic matter enriched at the brine-seawater interface.
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Affiliation(s)
- W Eder
- Lehrstuhl für Mikrobiologie und Archaeenzentrum, Universität Regensburg, D-93053 Regensburg, Germany.
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Cann IK, Stroot PG, Mackie KR, White BA, Mackie RI. Characterization of two novel saccharolytic, anaerobic thermophiles, Thermoanaerobacterium polysaccharolyticum sp. nov. and Thermoanaerobacterium zeae sp. nov., and emendation of the genus Thermoanaerobacterium. Int J Syst Evol Microbiol 2001; 51:293-302. [PMID: 11321073 DOI: 10.1099/00207713-51-2-293] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Two anaerobic, thermophilic, Gram-positive, non-spore forming bacteria with an array of polysaccharide-degrading enzymes were isolated from the leachate of a waste pile from a canning factory in Hoopeston, East Central Illinois, USA. The results of 16S rDNA sequence homology indicated that their closest relatives belong to the saccharolytic, thermophilic and anaerobic genera of Thermoanaerobacterium and Thermoanaerobacter. Although, the evolutionary distances between these bacteria and their closest relatives are greater than 11%, there is no defining phenotypic characteristic for the creation of a new genus. It is proposed that these bacteria should be placed in the genus Thermoanaerobacterium, which requires emendment of the genus description with regard to the reduction of thiosulfate to sulfur, because neither isolate is capable of this reduction. Thermoanaerobacterium polysaccharolyticum reduces thiosulfate to sulfide, whereas Thermoanaerobacterium zeae is unable to reduce thiosulfate. The cells of both isolates are rod-shaped and exist as single cells or sometimes in pairs. Cells are motile by means of flagella. Growth occurs between 45 and 72 degrees C, with optimum temperature of 65-68 degrees C at pH 6.8. The pH range for growth is from 4 to 8 at a temperature of 65 degrees C. Both organisms ferment glucose, arabinose, maltose, mannose, rhamnose, sucrose, trehalose, xylose, cellobiose, raffinose, melibiose and melezitose. The major end products of fermentation with glucose are ethanol and CO2, with lesser amounts of acetate, formate, lactate and hydrogen. The DNA G+C contents of Thermoanaerobacterium polysaccharolyticum sp. nov. and Thermoanaerobacterium zeae sp. nov. are 46 and 42 mol%, respectively. The type strains are KMTHCJT (= ATCC BAA-17T = DSM 13641T) and mel2T (= ATCC BAA-16T = DSM 13642T), respectively.
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Yamauchi KE, Snel J. Transmission electron microscopic demonstration of phagocytosis and intracellular processing of segmented filamentous bacteria by intestinal epithelial cells of the chick ileum. Infect Immun 2000; 68:6496-504. [PMID: 11035767 PMCID: PMC97741 DOI: 10.1128/iai.68.11.6496-6504.2000] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Segmented filamentous bacteria (SFB) are autochthonous bacteria colonizing the ileum of many young animals by attaching to intestinal epithelial cells. These nonpathogenic bacteria strongly stimulate the mucosal immune system and induce intestinal epithelial cells to express major histocompatibility complex class II molecules. We tried to discover whether SFB are phagocytized and intracellularly processed by the host cells, which is indicative of antigen processing. The middle part of the ileum was extracted from 10- and 20-day-old broiler chicks (Gallus gallus domesticus). Samples were processed and examined by scanning and transmission electron microscopy (SEM and TEM, respectively). In SEM, no, few, medium, and dense SFB colonization levels were classified. In TEM of cells from animals with medium or dense SFB colonization levels, we could observe extracellular particles ranging from those only indenting the cell membrane to particles found in the cytoplasmatic area beyond the terminal web. These particles had a structural similarity with SFB that were floating freely in the intestinal lumen. Furthermore, we observed unlacing of the membrane and septum surrounding the extracellular particles and their incorporation into host cytoplasmatic components, which strongly suggests that these particles are phagocytized and intracellularly processed SFB. This conclusion is supported by TEM analysis of samples with no or few SFB, in which we failed to find these characteristic morphologies. The phagocytosis process described here could be an important trigger for the stimulating effect of SFB on the mucosal immune system.
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Affiliation(s)
- K E Yamauchi
- Laboratory of Animal Science, Faculty of Agriculture, Kagawa University, Kagawa-ken 761-0795, Japan.
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Downes J, Olsvik B, Hiom SJ, Spratt DA, Cheeseman SL, Olsen I, Weightman AJ, Wade WG. Bulleidia extructa gen. nov., sp. nov., isolated from the oral cavity. Int J Syst Evol Microbiol 2000; 50 Pt 3:979-983. [PMID: 10843035 DOI: 10.1099/00207713-50-3-979] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Five strains of anaerobic non-sporing Gram-positive bacilli isolated from advanced periodontitis (four strains) and a dentoalveolar abscess (one strain) that did not correspond to existing species were subjected to phenotypic and genetic characterization. Following 16S rDNA sequence analysis, they were found to constitute a novel branch of the low G+C Gram-positive division of the phylogenetic tree related to Erysipelothrix rhusiopathiae and Holdemania filiformis. A new genus Bulleidia, and the species Bulleidia extructa, are proposed. Growth of B. extructa in broth media was poor but was enhanced by the addition of fructose, glucose or maltose together with Tween 80. Glucose and maltose were fermented and arginine was hydrolysed. Acetate, lactate and trace amounts of succinate were the end products of glucose fermentation. The G+C content of the DNA of the type strain is 38 mol%. The type strain of Bulleidia extructa is DSM 13220T.
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MESH Headings
- Bacteria, Anaerobic/classification
- Bacteria, Anaerobic/isolation & purification
- Bacteria, Anaerobic/metabolism
- Bacteria, Anaerobic/ultrastructure
- Base Composition
- DNA, Ribosomal/analysis
- DNA, Ribosomal/genetics
- Genes, rRNA
- Gram-Positive Asporogenous Rods/classification
- Gram-Positive Asporogenous Rods/isolation & purification
- Gram-Positive Asporogenous Rods/metabolism
- Gram-Positive Asporogenous Rods/ultrastructure
- Gram-Positive Bacterial Infections/microbiology
- Molecular Sequence Data
- Periapical Abscess/microbiology
- Periodontitis/microbiology
- Phylogeny
- RNA, Ribosomal, 16S/genetics
- Sequence Analysis, DNA
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Strous M, Fuerst JA, Kramer EH, Logemann S, Muyzer G, van de Pas-Schoonen KT, Webb R, Kuenen JG, Jetten MS. Missing lithotroph identified as new planctomycete. Nature 1999; 400:446-9. [PMID: 10440372 DOI: 10.1038/22749] [Citation(s) in RCA: 791] [Impact Index Per Article: 31.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
With the increased use of chemical fertilizers in agriculture, many densely populated countries face environmental problems associated with high ammonia emissions. The process of anaerobic ammonia oxidation ('anammox') is one of the most innovative technological advances in the removal of ammonia nitrogen from waste water. This new process combines ammonia and nitrite directly into dinitrogen gas. Until now, bacteria capable of anaerobically oxidizing ammonia had never been found and were known as "lithotrophs missing from nature". Here we report the discovery of this missing lithotroph and its identification as a new, autotrophic member of the order Planctomycetales, one of the major distinct divisions of the Bacteria. The new planctomycete grows extremely slowly, dividing only once every two weeks. At present, it cannot be cultivated by conventional microbiological techniques. The identification of this bacterium as the one responsible for anaerobic oxidation of ammonia makes an important contribution to the problem of unculturability.
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MESH Headings
- Ammonia/metabolism
- Bacteria/classification
- Bacteria/isolation & purification
- Bacteria/metabolism
- Bacteria/ultrastructure
- Bacteria, Anaerobic/classification
- Bacteria, Anaerobic/isolation & purification
- Bacteria, Anaerobic/metabolism
- Bacteria, Anaerobic/ultrastructure
- Biofilms/classification
- DNA, Bacterial/classification
- DNA, Bacterial/genetics
- Molecular Sequence Data
- Oxidation-Reduction
- Phylogeny
- RNA, Bacterial/classification
- RNA, Bacterial/genetics
- RNA, Ribosomal, 16S/classification
- RNA, Ribosomal, 16S/genetics
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Affiliation(s)
- M Strous
- Department of Biotechnology, Delft University of Technology, The Netherlands
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Nakazawa F, Poco SE, Ikeda T, Sato M, Kalfas S, Sundqvist G, Hoshino E. Cryptobacterium curtum gen. nov., sp. nov., a new genus of gram-positive anaerobic rod isolated from human oral cavities. Int J Syst Bacteriol 1999; 49 Pt 3:1193-200. [PMID: 10425779 DOI: 10.1099/00207713-49-3-1193] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Novel Eubacterium-like isolates, strains 12-3T and KV43-B, which were isolated from the periodontal pocket of an adult patient with periodontal disease and necrotic dental pulp, respectively, were studied taxonomically and phylogenetically. The morphological and differential biochemical characteristics of these organisms are also described in this paper. These organisms were Gram-positive, anaerobic, non-spore-forming, rod-shaped bacteria that were inert in most of the conventional biochemical tests and closely resembled members of asaccharolytic oral Eubacterium species. On the other hand, protein profiles of whole cells in SDS-PAGE and Western immunoblotting reaction analysis distinguished these isolates from strains of the previously described genus Eubacterium. The G+C content of the DNAs from the novel isolates was 50 and 51 mol%, respectively. The levels of DNA-DNA relatedness to other asaccharolytic oral Eubacterium species, including Eubacterium brachy, Eubacterium lentum, Eubacterium nodatum, Eubacterium timidum, Eubacterium saphenum, Eubacterium minutum and Eubacterium exiguum, was less than 11%. These organisms also exhibited a very low level of reassociation with the DNA of Eubacterium limosum, the type species of the genus Eubacterium. The results of 16S rDNA sequence comparisons revealed that these organisms represent a novel lineage distinct from all previously described genera of Gram-positive, rod-shaped bacteria. On the basis of our results, it is suggested that strains 12-3T and KV43-B should be classified in a new genus and species, for which the name Cryptobacterium curtum gen. nov., sp. nov. is proposed. The type strain of Cryptobacterium curtum is 12-3T (= ATCC 700683T).
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MESH Headings
- Adult
- Bacteria, Anaerobic/chemistry
- Bacteria, Anaerobic/classification
- Bacteria, Anaerobic/isolation & purification
- Bacteria, Anaerobic/ultrastructure
- Bacterial Proteins/chemistry
- Base Composition
- Blotting, Western
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- DNA, Bacterial/isolation & purification
- DNA, Ribosomal/chemistry
- DNA, Ribosomal/genetics
- DNA, Ribosomal/isolation & purification
- Electrophoresis, Polyacrylamide Gel
- Genes, rRNA
- Gram-Positive Asporogenous Rods/chemistry
- Gram-Positive Asporogenous Rods/classification
- Gram-Positive Asporogenous Rods/isolation & purification
- Gram-Positive Asporogenous Rods/ultrastructure
- Humans
- Molecular Sequence Data
- Nucleic Acid Hybridization
- Periodontal Diseases/microbiology
- Periodontal Pocket/microbiology
- Phylogeny
- RNA, Ribosomal, 16S/genetics
- Sequence Analysis, DNA
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Affiliation(s)
- F Nakazawa
- Department of Oral Microbiology, School of Dentistry, Niigata University, Japan
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Brechtel E, Matuschek M, Hellberg A, Egelseer EM, Schmid R, Bahl H. Cell wall of Thermoanaerobacterium thermosulfurigenes EM1: isolation of its components and attachment of the xylanase XynA. Arch Microbiol 1999; 171:159-65. [PMID: 10201095 DOI: 10.1007/s002030050694] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Thermoanaerobacterium thermosulfurigenes EM1 has a gram-positive type cell wall completely covered by a surface layer (S-layer) with hexagonal lattice symmetry. The components of the cell envelope were isolated, and the S-layer protein was purified and characterized. S-layer monomers assembled in vitro into sheets with the same hexagonal symmetry as in vivo. Monosaccharide analysis revealed that the S-layer is associated with fucose, rhamnose, mannosamine, glucosamine, galactose, and glucose. The N-terminal 31 amino acid residues of the S-layer protein showed significant similarity to SLH (S-layer homology) domains found in S-layer proteins of different bacteria and in the exocellular enzymes pullulanase, polygalacturonate hydrolase, and xylanase of T. thermosulfurigenes EM1. The xylanase from T. thermosulfurigenes EM1 was copurified with the S-layer protein during isolation of cell wall components. Since SLH domains of some structural proteins have been shown to anchor these proteins noncovalently to the cell envelope, we propose a common anchoring mechanism for the S-layer protein and exocellular enzymes via their SLH domains in the peptidoglycan-containing layer of T. thermosulfurigenes EM1.
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Affiliation(s)
- E Brechtel
- Abteilung Mikrobiologie, Universtität Rostock, Germany
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Abstract
Several barophilic Shewanella species have been isolated from deep-sea sediments at depths of 2,485-6,499 m. From the results of taxonomic studies, all of these isolates have been identified as strains of Shewanella benthica except for strain DSS12. Strain DSS12 is a member of a novel, moderately barophilic Shewanella species isolated from the Ryukyu Trench at a depth of 5,110 m. On Marine Agar 2216 plates, this organism produced a violet pigment, whereas the colonies of other isolates (S. benthica) were rose-colored. Phylogenetic analysis based on 16 S ribosomal RNA gene sequences showed that strain DSS12 represents a separate lineage within the genus Shewanella that is closely related to S. benthica and particularly to the members of the Shewanella barophiles branch. The temperature range for growth and some of the biochemical characteristics indicate that strain DSS12 differs from other Shewanella species. Furthermore, strain DSS12 displayed a low level of DNA similarity to the Shewanella type strains. Based on these differences, it is proposed that strain DSS12 represents a new deep-sea Shewanella species. The name Shewanella violacea (JCM 10179) is proposed.
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Affiliation(s)
- Y Nogi
- Deep Star Group, Japan Marine Science and Technology Center, Yokosuka, Japan
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Holliger C, Hahn D, Harmsen H, Ludwig W, Schumacher W, Tindall B, Vazquez F, Weiss N, Zehnder AJ. Dehalobacter restrictus gen. nov. and sp. nov., a strictly anaerobic bacterium that reductively dechlorinates tetra- and trichloroethene in an anaerobic respiration. Arch Microbiol 1998; 169:313-21. [PMID: 9531632 DOI: 10.1007/s002030050577] [Citation(s) in RCA: 240] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The highly enriched anaerobic bacterium that couples the reductive dechlorination of tetrachloroethene to growth, previously referred to as PER-K23, was obtained in pure culture and characterized. The bacterium, which does not form spores, is a small, gram-negative rod with one lateral flagellum. It utilized only H2 as an electron donor and tetrachloroethene and trichloroethene as electron acceptors in an anaerobic respiration process; it could not grow fermentatively. Acetate served as a carbon source in a defined medium containing iron as the sole trace element, the two vitamins thiamine and cyanocobalamin, and the three amino acids arginine, histidine, and threonine. The cells contained menaquinones and b-type cytochromes. The G+C content of the DNA was 45.3 +/- 0.3 mol%. The cell wall consisted of type-A3gamma peptidoglycan with ll-diaminopimelic acid and one glycine as an interpeptide bridge. The cells are surrounded by an S-layer; an outer membrane was absent. Comparative sequence analysis of the 16S rRNA sequence showed that PER-K23 is related to gram-positive bacteria with a low G+C content of the DNA. Based on the cytological, physiological, and phylogenetic characterization, it is proposed to affiliate the isolate to a new genus, Dehalobacter, with PER-K23 as the type strain of the new species Dehalobacter restrictus.
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Affiliation(s)
- C Holliger
- Swiss Federal Institute for Environmental Science and Technology (EAWAG), Limnological Research Center, CH-6047 Kastanienbaum, Switzerland.
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Newman DK, Kennedy EK, Coates JD, Ahmann D, Ellis DJ, Lovley DR, Morel FM. Dissimilatory arsenate and sulfate reduction in Desulfotomaculum auripigmentum sp. nov. Arch Microbiol 1997; 168:380-8. [PMID: 9325426 DOI: 10.1007/s002030050512] [Citation(s) in RCA: 130] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A newly discovered arsenate-reducing bacterium, strain OREX-4, differed significantly from strains MIT-13 and SES-3, the previously described arsenate-reducing isolates, which grew on nitrate but not on sulfate. In contrast, strain OREX-4 did not respire nitrate but grew on lactate, with either arsenate or sulfate serving as the electron acceptor, and even preferred arsenate. Both arsenate and sulfate reduction were inhibited by molybdate. Strain OREX-4, a gram-positive bacterium with a hexagonal S-layer on its cell wall, metabolized compounds commonly used by sulfate reducers. Scorodite (FeAsO42. H2O) an arsenate-containing mineral, provided micromolar concentrations of arsenate that supported cell growth. Physiologically and phylogenetically, strain OREX-4 was far-removed from strains MIT-13 and SES-3: strain OREX-4 grew on different electron donors and electron acceptors, and fell within the gram-positive group of the Bacteria, whereas MIT-13 and SES-3 fell together in the epsilon-subdivision of the Proteobacteria. Together, these results suggest that organisms spread among diverse bacterial phyla can use arsenate as a terminal electron acceptor, and that dissimilatory arsenate reduction might occur in the sulfidogenic zone at arsenate concentrations of environmental interest. 16S rRNA sequence analysis indicated that strain OREX-4 is a new species of the genus Desulfotomaculum, and accordingly, the name Desulfotomaculum auripigmentum is proposed.
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Affiliation(s)
- D K Newman
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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45
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Tarlera S, Muxí L, Soubes M, Stams AJ. Caloramator proteoclasticus sp. nov., a new moderately thermophilic anaerobic proteolytic bacterium. Int J Syst Bacteriol 1997; 47:651-6. [PMID: 9226895 DOI: 10.1099/00207713-47-3-651] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A new moderately thermophilic proteolytic anaerobe, strain UT, was isolated from mesophilic granular methanogenic sludge. The cells were spore-forming, motile rods that were 0.4 micron wide and 2.4 to 4 microns long and stained gram negative. Electron micrographs of thin sections revealed the presence of an atypical gram-positive cell wall. Optimum growth occurred at 55 degrees C and at pH values between 7.0 and 7.5, with a doubling time of 30 min. The DNA base ratio of guanine plus cytosine was 31 mol%. The bacterium fermented proteins mainly to acetate, hydrogen, formate, and branched-chain fatty acids. Several amino acids, including glutamate, aspartate, arginine, histidine, threonine, methionine, and branched-chain amino acids, were also utilized. Glutamate was degraded to acetate, formate, hydrogen, and alanine. In addition, the strain degraded carbohydrates, including glucose, fructose, mannose, cellobiose, and starch, to acetate, ethanol, formate, lactate, and hydrogen. The results of a 16S rRNA sequence analysis phylogenetically placed strain UT in the low-guanine-plus-cytosine-content subgroup of the gram-positive phylum. We propose to classify the described strain in the genus Caloramator as a new species, Caloramator proteoclasticus. The type strain of C. proteoclasticus, strain U, has been deposited in the Deutsche Sammlung von Mikroorganismen as strain DSM 10124.
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Affiliation(s)
- S Tarlera
- Departamento de Microbiología, Facultad de Química, Universidad de la República, Montevideo, Uruguay.
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46
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Takahata M, Nishino T. Antibacterial activities of tosufloxacin against anaerobic bacteria and the electron micrograph of its bactericidal effects. Chemotherapy 1997; 43:153-8. [PMID: 9142454 DOI: 10.1159/000239551] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Tosufloxacin, a quinolone, showed a broad antibacterial spectrum against gram-positive and gram-negative bacteria including anaerobic bacteria. Tosufloxacin was 4- to 8-fold more active than levofloxacin and ciprofloxacin. The MIC90 of tosufloxacin for clinical isolates of Bacteroides fragilis, Bacteroides vulgatus, Bacteroides thetaiotaomicron and Peptostreptococcus asaccharolyticus were 0.78, 0.39, 1.56 and 0.39 micrograms/ml, respectively. Morphological observation with the scanning and transmission electron microscope revealed that exposure of B. fragilis ATCC 25285 to tosufloxacin resulted in the formation of filamentous cells with mesosome-like structures. Tosufloxacin also induced the mini-cell resulting from the unusual cell division system and a number of holes in the outer membrane. Tosufloxacin at 4 MIC caused some change in cell wall organization and cell lysis. After exposure of P. asaccharolyticus ATCC 14953 to tosufloxacin, the cells increased considerably in size and the cell wall and cross wall thickening was observed.
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Affiliation(s)
- M Takahata
- Department of Microbiology, Kyoto Pharmaceutical University, Japan
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47
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Abstract
Initial reactions in anaerobic oxidation of ethylbenzene were investigated in a denitrifying bacterium, strain EB1. Cells of strain EB1 mineralized ethylbenzene to CO2 under denitrifying conditions, as demonstrated by conversion of 69% of [14C]ethylbenzene to 14CO2. In anaerobic suspensions of strain EB1 cells metabolizing ethylbenzene, the transient formation and consumption of 1-phenylethanol, acetophenone, and an as yet unidentified compound were observed. On the basis of growth experiments and spectroscopic data, the unknown compound is proposed to be benzoyl acetate. Cell suspension experiments using H2(18)O demonstrated that the hydroxyl group of the first product of anoxic ethylbenzene oxidation, 1-phenylethanol, is derived from water. A tentative pathway for anaerobic ethylbenzene mineralization by strain EB1 is proposed.
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Affiliation(s)
- H A Ball
- Western Region Hazardous Substance Research Center, Stanford University, California 94305-4020, USA
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48
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Stetter KO. Hyperthermophiles in the history of life. Ciba Found Symp 1996; 202:1-10; discussion 11-8. [PMID: 9243007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Prokaryotes requiring extremely high growth temperatures (optimum 80-110 degrees C) have recently been isolated from water-containing terrestrial, subterranean and submarine high temperature environments. These hyperthermophiles consist of primary producers and consumers of organic matter, forming unique high temperature ecosystems. Surprisingly, within the 16S rRNA-based phylogenetic tree, hyperthermophiles occupy all the shortest and deepest branches closest to the root. Therefore, they appear to be the most primitive extant organisms. Most of them (the primary producers) are able to grow chemolithoautotrophically, using CO2 as sole carbon source and inorganic energy sources, suggesting a hyperthermophilic autotrophic common ancestor. They gain energy from various kinds of respiration. Molecular hydrogen and reduced sulfur compounds serve as electron donors while CO2, oxidized sulfur compounds, NO3- and O2 (only rarely) serve as electron acceptors. Growth demands of hyperthermophiles fit the scenario of a hot volcanism-dominated primitive Earth. Similar anaerobic chemolithoautotrophic hyperthermophiles, completely independent of a sun, could even exist on other planets provided that active volcanism and liquid water were present.
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Affiliation(s)
- K O Stetter
- Lehrstuhl für Mikrobiologie, Universität Regensburg, Germany
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49
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Zhilina TN, Zavarzin GA, Rainey F, Kevbrin VV, Kostrikina NA, Lysenko AM. Spirochaeta alkalica sp. nov., Spirochaeta africana sp. nov., and Spirochaeta asiatica sp. nov., alkaliphilic anaerobes from the Continental Soda Lakes in Central Asia and the East African Rift. Int J Syst Bacteriol 1996; 46:305-12. [PMID: 8573509 DOI: 10.1099/00207713-46-1-305] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
During a study of microbial communities in athalassic bodies of water, three new species within the genus Spirochaeta were described. These are alkaliphilic Spirochaeta alkalica sp. nov. Z-7491 (DSM 8900) and halophilic S. africana sp. nov. Z-7692 (DSM 8902) from the soda-depositing Lake Magadi in Central Africa and haloalkaliphilic S. asiatica sp. nov. Z-7591 (DSM 8901) from Lake Khatyn, Central Asia. These mesophilic spirochetes develop at pHs of > 9 as anaerobic saccharolytic dissipotrophs. The DNA base compositions (moles percent G+C) of the strains were as follows: S. alkalica Z-7491, 57.1; S. africana Z-7692, 56.1; and S. asiatica Z-7591, 49.2. The optimum growth parameters (temperature, pH, and NaCl concentration [percent, wt/vol], respectively) were as follows: for S. alkalica Z-7491, 35 degrees C, 9.2, and 5 to 7%; for S. africana Z-7692, 35 degrees C, 9.3, and 5 to 7%; and for S. asiatica Z-7591, 35 degrees C, 8.9, and 3 to 6%. The products of glucose fermentation were acetate, hydrogen, ethanol, and lactate, in different proportions, for S. alkalica and S. africana; for S. asiatica, they were acetate, ethanol, and lactate. S. asiatica is strictly anaerobic, while S. alkalica and S. africana are rather aerotolerant. All three species group within the radiation of the majority of the species of the genus Spirochaeta. Studies of the genes encoding 16S rRNA indicate a possible fanning out of the phylogenetic tree of spirochetes.
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Affiliation(s)
- T N Zhilina
- Institute of Microbiology RAS, Moscow, Russia
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50
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Aagnes TH, Sørmo W, Mathiesen SD. Ruminal microbial digestion in free-living, in captive lichen-fed, and in starved reindeer (Rangifer tarandus tarandus) in winter. Appl Environ Microbiol 1995; 61:583-91. [PMID: 7574599 PMCID: PMC167322 DOI: 10.1128/aem.61.2.583-591.1995] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
In free-living (FL) reindeer eating a natural mixed winter diet dominated by lichens, captive (CF) reindeer fed pure lichens ad libitum, and CF reindeer subsequently starved for 1 day (CS1 reindeer) or 4 days (CS4 reindeer), the dominant rumen anaerobic bacteria were characterized, their population densities were estimated, and ruminal pH and volatile fatty acid concentrations were determined. In the FL reindeer, the total median viable anaerobic bacterial population ranged from 18 x 10(8) to 35 x 10(8) cells per ml of rumen fluid (n = 4), compared with 26 x 10(8) to 34 x 10(8) and 0.09 x 10(8) to 0.1 x 10(8) cells per ml of rumen fluid in CF reindeer (n = 2) and CS4 reindeer (n = 2), respectively. The median bacterial population adhering to the rumen solids ranged from 260 x 10(8) to 450 x 10(8), 21 x 10(8) to 38 x 10(8), and 0.5 x 10(8) cells per g (wet weight) of rumen solids in FL, CF, and CS4 reindeer, respectively. Although there were variations in the rumen bacterial composition among the FL reindeer (n = 4), strains of Bacteroides, Fibrobacter, Streptococcus, and Clostridium dominated in the rumen fluid. Streptococcus spp. and Clostridium spp. were the dominant bacteria in the CF reindeer (n = 2), while in the CS4 reindeer (n = 2) the dominant bacteria were Fusobacterium spp., members of the family Enterobacteriaceae, and Eubacterium spp. Transmission electron micrographs of lichen particles from the rumen of one FL reindeer, one CF reindeer, and one CS4 reindeer show bacteria resembling Bacteroides spp. adhering to the lichen particles, evidently digesting the lichen hyphae from the inside.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- T H Aagnes
- Department of Arctic Biology, University of Tromsø, Norway
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